Large scale longitudinal study on student sleep and changed start times out of Colorado

I'd missed that this had been released last week:

Since many districts stagger their school buses in order to pick up everyone, the elementary school students began school an hour earlier over the course of the study so that older students could be picked up later, said study author Lisa Meltzer, a pediatric psychologist at National Jewish Health in Colorado.

She said the research team found no significant difference in elementary school students' sleep times after the hour change.

The middle schools delayed their start times by 40 to 60 minutes, and high schools delayed theirs by 70 minutes to ensure they started at or after 8:30 a.m.

Middle school students went to bed an average of nine minutes later, but slept in an additional 37 minutes, giving them an average of 29 minutes of extra sleep. High school students went to bed an average of 14 minutes later, but slept for an additional 60 minutes, allowing them to sleep 46 minutes more on average.

That's from CNN reporting on the study itself (linked above).  Some additional links here. 

Editing to add that Massachusetts House bill H.663 would study this issue (and could use co-sponsors!).